Nagios Core before 4.5.13 and Nagios XI before 2026R1.5 are vulnerable to authenticated remote code execution via custom-variable macro injection through the Nagios Remote Data Processor (NRDP). When a custom variable defined on a host, service, or contact is referenced in a shell-executed command line, an authenticated attacker with NRDP access can inject OS commands through the macro value. Exploitation requires a non-default configuration in which a custom variable is defined and referenced in a shell-executed command.
https://www.nagios.com/security-disclosures/nagios-core/
https://github.com/NagiosEnterprises/nagioscore/blob/master/Changelog
Published: 2026-08-12
Updated: 2026-08-12
Base Score: 7.1
Vector: CVSS2#AV:N/AC:H/Au:S/C:C/I:C/A:C
Severity: High
Base Score: 7.5
Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity: High
Base Score: 7.7
Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Severity: High